Remove skin from chicken and shred meat into large pieces. Set aside.
In a small frying pan, add vegetable oil and heat over medium heat. When oil is hot, add chopped onions and sauté until soft.
In a large pot or Dutch oven, add broth, poultry seasoning, salt, pepper, carrots, celery, and sautéed onions. Bring to a boil. Reduce to simmer for about 10 minutes to soften vegetables, and then add shredded chicken. Continue to simmer while making dumplings.
While stew is simmering, prepare dumplings. Open can and remove biscuits. On a lightly floured surface, roll each biscuit to 1/4 inch thick. With a knife, cut each biscuit into 4 pie-pieces. Set aside.
Skin surface for any scum that has risen to top. Stir in chicken gravy.
With the stew still simmering over low heat, stir in dumplings a few at a time. Once all dumplings are in the pot, cover with a tight fitting lid and cook for 10 minutes. Ladle into bowls and serve piping hot.